1. Field of the Invention
The present invention relates to an electric energy consumption control system and an electric energy consumption control method that control electric energy consumption of an image forming apparatus. Particularly, the present invention relates to the electric energy consumption control system, the electric energy consumption control method, and a storage medium storing control program therefor, which are capable of controlling electric energy consumption of an apparatus for each of users based on a target electric energy consumption in a fixed period set by each of the users to operate the apparatus by expected electric energy consumption while balancing needs of the users.
2. Description of the Related Art
In general, there is a known electric energy consumption control technique that establishes a target electric energy consumption as a reference value with respect to electric energy consumption of an image forming apparatus and that shifts an operation mode to a power saving mode with which the image forming apparatus is provided based on the reference value.
Japanese Laid-Open Patent Publication (Kokai) No. 2008-245401 (JP 2008-245401A) discloses a power control system that uses such a electric energy consumption control technique and that includes image forming apparatuses used by users. The power control system establishes a reference value for electric energy consumption in a predetermined period for each of the users and has a function for restricting the uses by a user whose electric energy consumption exceeded his or her reference value.
The conventional power control system merely restricts the use of the user whose electric energy consumption exceeds the reference value until expiring the period, but cannot control the total electric energy consumed by all the users.
Moreover, in the conventional power control system, the value that totaled the reference values of all the users is a target value of the entire control system, and the total amount of the resultant electric energy of all the users is an entire-system result value. Accordingly, in the conventional power control system, when there are many users whose resultant electric energy does not reach the reference value, the entire-system result value may be adequately lower than the target value of the entire control system. However, even when there is such a margin, a user whose resultant electric energy exceeded the reference value is restricted to use.